[Show abstract][Hide abstract] ABSTRACT: We developed a semi-automated tool to quantify emphysema from thoracic X-ray multi-detector (64-slice) computed tomography (CT) for training purposes and multi-reader studies.
Thoracic X-ray CT was acquired in 93 ex-smokers, who were evaluated by six trainees with little or no expertise (trainees) and a single experienced thoracic radiologist (expert). A graphic user interface (GUI) was developed for emphysema quantification based on the percentile of lung where a score of 0=no abnormalities, 1=1-25%, 2=26-50%, 3=51-75% and 4=76-100% for each lung side/slice. Trainees blinded to subject characteristics scored randomized images twice; accuracy was determined by comparison to expert scores, density histogram 15th percentile (HU15), relative area at -950HU (RA950), low attenuation clusters at -950HU (LAC950), -856HU (LAC856) and the diffusing capacity for carbon monoxide (DLCO%pred). Intra- and inter-observer reproducibility was evaluated using coefficients-of-variation (COV), intra-class (ICC) and Pearson correlations.
Trainee-expert correlations were significant (r=0.85-0.97, p<0.0001) and a significant trainee bias (0.15±0.22) was observed. Emphysema score was correlated with RA950 (r=0.88, p<0.0001), HU15 (r=-0.77, p<0.0001), LAC950 (r=0.76, p<0.0001), LAC856 (r=0.74, p=0.0001) and DLCO%pred (r=-0.71, p<0.0001). Intra-observer reproducibility (COV=4-27%; ICC=0.75-0.94) was moderate to high for trainees; intra- and inter-observer COV were negatively and non-linearly correlated with emphysema score.
We developed a GUI for rapid and interactive emphysema scoring that allows for comparison of multiple readers with clinical and radiological standards.
Full-text · Article · Aug 2013 · European journal of radiology
[Show abstract][Hide abstract] ABSTRACT: We present an unusual case of extensive avascular malformations (AVMs) causing non-cirrhotic portal hypertension. This phenomenon, though previously described, is a rare clinical entity which, in the setting of life threatening portal hypertension, may require vascular decompression either by surgery or a transjugular intrahepatic portosystemic shunt.
No preview · Article · Jul 2012 · Annals of hepatology: official journal of the Mexican Association of Hepatology